C# Count occurrences in list

Question

I have a type Card with an int property called Value where Ace = 14, Five = 5, etc.

If I have a list of Cards (5), ie. a hand. What I would like to do is count the number cards where the Value is equal to another card, Ie Finding 4 of a kind, 3 of a kind, a pair, two pair etc. I'm fairly new to C#/programming, but I believe this is a case for LINQ/Lambda expression? Can someone help me out?

class Card : IComparable<Card>
{
    private string name;
    private int value;
    private string suit;
    public int Value 
    { 
        get
        {
            return value;
        } 
    }
    <.....> 
    //Constructor accepts string ex. "AH" and builds value 14, suit "Hearts" 
    public int CompareTo(Card that)
    {
        if (this.value > that.value) return -1;
        if (this.value == that.value) return 0;
        return 1;
    }
}
List<Card> HandBuilder = new List<Card>();
HandBuilder.Add(...); //5 Cards
HandBuilder.Count ??   //Help

Answer 1

It's pretty trivial using GroupBy .

var cards = HandBuilder.GroupBy(card => card.Value)
    .OrderByDescending(group => group.Count());

To check for four of a kind just see if the first group has four items; to check for three of a kind see if the first group has three items. To check for two pair just see if the first two groups each have two items.